run-command: use BUG() to report bugs, not die()
[git/git.git] / pack-bitmap.c
CommitLineData
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1#include "cache.h"
2#include "commit.h"
3#include "tag.h"
4#include "diff.h"
5#include "revision.h"
6#include "progress.h"
7#include "list-objects.h"
8#include "pack.h"
9#include "pack-bitmap.h"
10#include "pack-revindex.h"
11#include "pack-objects.h"
0317f455 12#include "packfile.h"
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13#include "repository.h"
14#include "object-store.h"
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15
16/*
17 * An entry on the bitmap index, representing the bitmap for a given
18 * commit.
19 */
20struct stored_bitmap {
21 unsigned char sha1[20];
22 struct ewah_bitmap *root;
23 struct stored_bitmap *xor;
24 int flags;
25};
26
27/*
28 * The currently active bitmap index. By design, repositories only have
29 * a single bitmap index available (the index for the biggest packfile in
30 * the repository), since bitmap indexes need full closure.
31 *
32 * If there is more than one bitmap index available (e.g. because of alternates),
33 * the active bitmap index is the largest one.
34 */
35static struct bitmap_index {
36 /* Packfile to which this bitmap index belongs to */
37 struct packed_git *pack;
38
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39 /*
40 * Mark the first `reuse_objects` in the packfile as reused:
41 * they will be sent as-is without using them for repacking
42 * calculations
43 */
44 uint32_t reuse_objects;
45
46 /* mmapped buffer of the whole bitmap index */
47 unsigned char *map;
48 size_t map_size; /* size of the mmaped buffer */
49 size_t map_pos; /* current position when loading the index */
50
51 /*
52 * Type indexes.
53 *
54 * Each bitmap marks which objects in the packfile are of the given
55 * type. This provides type information when yielding the objects from
56 * the packfile during a walk, which allows for better delta bases.
57 */
58 struct ewah_bitmap *commits;
59 struct ewah_bitmap *trees;
60 struct ewah_bitmap *blobs;
61 struct ewah_bitmap *tags;
62
25143a54 63 /* Map from SHA1 -> `stored_bitmap` for all the bitmapped commits */
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64 khash_sha1 *bitmaps;
65
66 /* Number of bitmapped commits */
67 uint32_t entry_count;
68
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69 /* Name-hash cache (or NULL if not present). */
70 uint32_t *hashes;
71
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72 /*
73 * Extended index.
74 *
75 * When trying to perform bitmap operations with objects that are not
76 * packed in `pack`, these objects are added to this "fake index" and
77 * are assumed to appear at the end of the packfile for all operations
78 */
79 struct eindex {
80 struct object **objects;
81 uint32_t *hashes;
82 uint32_t count, alloc;
83 khash_sha1_pos *positions;
84 } ext_index;
85
86 /* Bitmap result of the last performed walk */
87 struct bitmap *result;
88
89 /* Version of the bitmap index */
90 unsigned int version;
91
92 unsigned loaded : 1;
93
94} bitmap_git;
95
96static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
97{
98 struct ewah_bitmap *parent;
99 struct ewah_bitmap *composed;
100
101 if (st->xor == NULL)
102 return st->root;
103
104 composed = ewah_pool_new();
105 parent = lookup_stored_bitmap(st->xor);
106 ewah_xor(st->root, parent, composed);
107
108 ewah_pool_free(st->root);
109 st->root = composed;
110 st->xor = NULL;
111
112 return composed;
113}
114
115/*
116 * Read a bitmap from the current read position on the mmaped
117 * index, and increase the read position accordingly
118 */
119static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)
120{
121 struct ewah_bitmap *b = ewah_pool_new();
122
123 int bitmap_size = ewah_read_mmap(b,
124 index->map + index->map_pos,
125 index->map_size - index->map_pos);
126
127 if (bitmap_size < 0) {
128 error("Failed to load bitmap index (corrupted?)");
129 ewah_pool_free(b);
130 return NULL;
131 }
132
133 index->map_pos += bitmap_size;
134 return b;
135}
136
137static int load_bitmap_header(struct bitmap_index *index)
138{
139 struct bitmap_disk_header *header = (void *)index->map;
140
141 if (index->map_size < sizeof(*header) + 20)
142 return error("Corrupted bitmap index (missing header data)");
143
144 if (memcmp(header->magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE)) != 0)
145 return error("Corrupted bitmap index file (wrong header)");
146
147 index->version = ntohs(header->version);
148 if (index->version != 1)
149 return error("Unsupported version for bitmap index file (%d)", index->version);
150
151 /* Parse known bitmap format options */
152 {
153 uint32_t flags = ntohs(header->options);
154
155 if ((flags & BITMAP_OPT_FULL_DAG) == 0)
156 return error("Unsupported options for bitmap index file "
157 "(Git requires BITMAP_OPT_FULL_DAG)");
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158
159 if (flags & BITMAP_OPT_HASH_CACHE) {
160 unsigned char *end = index->map + index->map_size - 20;
161 index->hashes = ((uint32_t *)end) - index->pack->num_objects;
162 }
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163 }
164
165 index->entry_count = ntohl(header->entry_count);
166 index->map_pos += sizeof(*header);
167 return 0;
168}
169
170static struct stored_bitmap *store_bitmap(struct bitmap_index *index,
171 struct ewah_bitmap *root,
172 const unsigned char *sha1,
173 struct stored_bitmap *xor_with,
174 int flags)
175{
176 struct stored_bitmap *stored;
177 khiter_t hash_pos;
178 int ret;
179
180 stored = xmalloc(sizeof(struct stored_bitmap));
181 stored->root = root;
182 stored->xor = xor_with;
183 stored->flags = flags;
184 hashcpy(stored->sha1, sha1);
185
186 hash_pos = kh_put_sha1(index->bitmaps, stored->sha1, &ret);
187
188 /* a 0 return code means the insertion succeeded with no changes,
189 * because the SHA1 already existed on the map. this is bad, there
190 * shouldn't be duplicated commits in the index */
191 if (ret == 0) {
192 error("Duplicate entry in bitmap index: %s", sha1_to_hex(sha1));
193 return NULL;
194 }
195
196 kh_value(index->bitmaps, hash_pos) = stored;
197 return stored;
198}
199
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200static inline uint32_t read_be32(const unsigned char *buffer, size_t *pos)
201{
202 uint32_t result = get_be32(buffer + *pos);
203 (*pos) += sizeof(result);
204 return result;
205}
206
207static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
208{
209 return buffer[(*pos)++];
210}
211
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212#define MAX_XOR_OFFSET 160
213
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214static int load_bitmap_entries_v1(struct bitmap_index *index)
215{
fff42755 216 uint32_t i;
599dc766 217 struct stored_bitmap *recent_bitmaps[MAX_XOR_OFFSET] = { NULL };
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218
219 for (i = 0; i < index->entry_count; ++i) {
220 int xor_offset, flags;
221 struct ewah_bitmap *bitmap = NULL;
222 struct stored_bitmap *xor_bitmap = NULL;
223 uint32_t commit_idx_pos;
224 const unsigned char *sha1;
225
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226 commit_idx_pos = read_be32(index->map, &index->map_pos);
227 xor_offset = read_u8(index->map, &index->map_pos);
228 flags = read_u8(index->map, &index->map_pos);
fff42755 229
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230 sha1 = nth_packed_object_sha1(index->pack, commit_idx_pos);
231
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232 bitmap = read_bitmap_1(index);
233 if (!bitmap)
234 return -1;
235
236 if (xor_offset > MAX_XOR_OFFSET || xor_offset > i)
237 return error("Corrupted bitmap pack index");
238
239 if (xor_offset > 0) {
240 xor_bitmap = recent_bitmaps[(i - xor_offset) % MAX_XOR_OFFSET];
241
242 if (xor_bitmap == NULL)
243 return error("Invalid XOR offset in bitmap pack index");
244 }
245
246 recent_bitmaps[i % MAX_XOR_OFFSET] = store_bitmap(
247 index, bitmap, sha1, xor_bitmap, flags);
248 }
249
250 return 0;
251}
252
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253static char *pack_bitmap_filename(struct packed_git *p)
254{
9ae97018 255 size_t len;
cb468050 256
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257 if (!strip_suffix(p->pack_name, ".pack", &len))
258 die("BUG: pack_name does not end in .pack");
259 return xstrfmt("%.*s.bitmap", (int)len, p->pack_name);
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260}
261
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262static int open_pack_bitmap_1(struct packed_git *packfile)
263{
264 int fd;
265 struct stat st;
266 char *idx_name;
267
268 if (open_pack_index(packfile))
269 return -1;
270
271 idx_name = pack_bitmap_filename(packfile);
a5436b57 272 fd = git_open(idx_name);
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273 free(idx_name);
274
275 if (fd < 0)
276 return -1;
277
278 if (fstat(fd, &st)) {
279 close(fd);
280 return -1;
281 }
282
283 if (bitmap_git.pack) {
284 warning("ignoring extra bitmap file: %s", packfile->pack_name);
285 close(fd);
286 return -1;
287 }
288
289 bitmap_git.pack = packfile;
290 bitmap_git.map_size = xsize_t(st.st_size);
291 bitmap_git.map = xmmap(NULL, bitmap_git.map_size, PROT_READ, MAP_PRIVATE, fd, 0);
292 bitmap_git.map_pos = 0;
293 close(fd);
294
295 if (load_bitmap_header(&bitmap_git) < 0) {
296 munmap(bitmap_git.map, bitmap_git.map_size);
297 bitmap_git.map = NULL;
298 bitmap_git.map_size = 0;
299 return -1;
300 }
301
302 return 0;
303}
304
305static int load_pack_bitmap(void)
306{
307 assert(bitmap_git.map && !bitmap_git.loaded);
308
309 bitmap_git.bitmaps = kh_init_sha1();
310 bitmap_git.ext_index.positions = kh_init_sha1_pos();
9d98bbf5 311 load_pack_revindex(bitmap_git.pack);
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312
313 if (!(bitmap_git.commits = read_bitmap_1(&bitmap_git)) ||
314 !(bitmap_git.trees = read_bitmap_1(&bitmap_git)) ||
315 !(bitmap_git.blobs = read_bitmap_1(&bitmap_git)) ||
316 !(bitmap_git.tags = read_bitmap_1(&bitmap_git)))
317 goto failed;
318
319 if (load_bitmap_entries_v1(&bitmap_git) < 0)
320 goto failed;
321
322 bitmap_git.loaded = 1;
323 return 0;
324
325failed:
326 munmap(bitmap_git.map, bitmap_git.map_size);
327 bitmap_git.map = NULL;
328 bitmap_git.map_size = 0;
329 return -1;
330}
331
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332static int open_pack_bitmap(void)
333{
334 struct packed_git *p;
335 int ret = -1;
336
337 assert(!bitmap_git.map && !bitmap_git.loaded);
338
a80d72db 339 for (p = get_packed_git(the_repository); p; p = p->next) {
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340 if (open_pack_bitmap_1(p) == 0)
341 ret = 0;
342 }
343
344 return ret;
345}
346
347int prepare_bitmap_git(void)
348{
349 if (bitmap_git.loaded)
350 return 0;
351
352 if (!open_pack_bitmap())
353 return load_pack_bitmap();
354
355 return -1;
356}
357
358struct include_data {
359 struct bitmap *base;
360 struct bitmap *seen;
361};
362
363static inline int bitmap_position_extended(const unsigned char *sha1)
364{
365 khash_sha1_pos *positions = bitmap_git.ext_index.positions;
366 khiter_t pos = kh_get_sha1_pos(positions, sha1);
367
368 if (pos < kh_end(positions)) {
369 int bitmap_pos = kh_value(positions, pos);
370 return bitmap_pos + bitmap_git.pack->num_objects;
371 }
372
373 return -1;
374}
375
376static inline int bitmap_position_packfile(const unsigned char *sha1)
377{
378 off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
379 if (!offset)
380 return -1;
381
9d98bbf5 382 return find_revindex_position(bitmap_git.pack, offset);
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383}
384
385static int bitmap_position(const unsigned char *sha1)
386{
387 int pos = bitmap_position_packfile(sha1);
388 return (pos >= 0) ? pos : bitmap_position_extended(sha1);
389}
390
391static int ext_index_add_object(struct object *object, const char *name)
392{
393 struct eindex *eindex = &bitmap_git.ext_index;
394
395 khiter_t hash_pos;
396 int hash_ret;
397 int bitmap_pos;
398
ed1c9977 399 hash_pos = kh_put_sha1_pos(eindex->positions, object->oid.hash, &hash_ret);
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400 if (hash_ret > 0) {
401 if (eindex->count >= eindex->alloc) {
402 eindex->alloc = (eindex->alloc + 16) * 3 / 2;
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403 REALLOC_ARRAY(eindex->objects, eindex->alloc);
404 REALLOC_ARRAY(eindex->hashes, eindex->alloc);
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405 }
406
407 bitmap_pos = eindex->count;
408 eindex->objects[eindex->count] = object;
409 eindex->hashes[eindex->count] = pack_name_hash(name);
410 kh_value(eindex->positions, hash_pos) = bitmap_pos;
411 eindex->count++;
412 } else {
413 bitmap_pos = kh_value(eindex->positions, hash_pos);
414 }
415
416 return bitmap_pos + bitmap_git.pack->num_objects;
417}
418
de1e67d0 419static void show_object(struct object *object, const char *name, void *data)
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420{
421 struct bitmap *base = data;
422 int bitmap_pos;
423
ed1c9977 424 bitmap_pos = bitmap_position(object->oid.hash);
fff42755 425
de1e67d0 426 if (bitmap_pos < 0)
fff42755 427 bitmap_pos = ext_index_add_object(object, name);
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428
429 bitmap_set(base, bitmap_pos);
430}
431
432static void show_commit(struct commit *commit, void *data)
433{
434}
435
436static int add_to_include_set(struct include_data *data,
437 const unsigned char *sha1,
438 int bitmap_pos)
439{
440 khiter_t hash_pos;
441
442 if (data->seen && bitmap_get(data->seen, bitmap_pos))
443 return 0;
444
445 if (bitmap_get(data->base, bitmap_pos))
446 return 0;
447
448 hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
449 if (hash_pos < kh_end(bitmap_git.bitmaps)) {
450 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
451 bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
452 return 0;
453 }
454
455 bitmap_set(data->base, bitmap_pos);
456 return 1;
457}
458
459static int should_include(struct commit *commit, void *_data)
460{
461 struct include_data *data = _data;
462 int bitmap_pos;
463
ed1c9977 464 bitmap_pos = bitmap_position(commit->object.oid.hash);
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465 if (bitmap_pos < 0)
466 bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
467
ed1c9977 468 if (!add_to_include_set(data, commit->object.oid.hash, bitmap_pos)) {
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469 struct commit_list *parent = commit->parents;
470
471 while (parent) {
472 parent->item->object.flags |= SEEN;
473 parent = parent->next;
474 }
475
476 return 0;
477 }
478
479 return 1;
480}
481
482static struct bitmap *find_objects(struct rev_info *revs,
483 struct object_list *roots,
484 struct bitmap *seen)
485{
486 struct bitmap *base = NULL;
487 int needs_walk = 0;
488
489 struct object_list *not_mapped = NULL;
490
491 /*
492 * Go through all the roots for the walk. The ones that have bitmaps
493 * on the bitmap index will be `or`ed together to form an initial
494 * global reachability analysis.
495 *
496 * The ones without bitmaps in the index will be stored in the
497 * `not_mapped_list` for further processing.
498 */
499 while (roots) {
500 struct object *object = roots->item;
501 roots = roots->next;
502
503 if (object->type == OBJ_COMMIT) {
ed1c9977 504 khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->oid.hash);
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505
506 if (pos < kh_end(bitmap_git.bitmaps)) {
507 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
508 struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
509
510 if (base == NULL)
511 base = ewah_to_bitmap(or_with);
512 else
513 bitmap_or_ewah(base, or_with);
514
515 object->flags |= SEEN;
516 continue;
517 }
518 }
519
520 object_list_insert(object, &not_mapped);
521 }
522
523 /*
524 * Best case scenario: We found bitmaps for all the roots,
525 * so the resulting `or` bitmap has the full reachability analysis
526 */
527 if (not_mapped == NULL)
528 return base;
529
530 roots = not_mapped;
531
532 /*
533 * Let's iterate through all the roots that don't have bitmaps to
534 * check if we can determine them to be reachable from the existing
535 * global bitmap.
536 *
537 * If we cannot find them in the existing global bitmap, we'll need
538 * to push them to an actual walk and run it until we can confirm
539 * they are reachable
540 */
541 while (roots) {
542 struct object *object = roots->item;
543 int pos;
544
545 roots = roots->next;
ed1c9977 546 pos = bitmap_position(object->oid.hash);
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547
548 if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
549 object->flags &= ~UNINTERESTING;
550 add_pending_object(revs, object, "");
551 needs_walk = 1;
552 } else {
553 object->flags |= SEEN;
554 }
555 }
556
557 if (needs_walk) {
558 struct include_data incdata;
559
560 if (base == NULL)
561 base = bitmap_new();
562
563 incdata.base = base;
564 incdata.seen = seen;
565
566 revs->include_check = should_include;
567 revs->include_check_data = &incdata;
568
569 if (prepare_revision_walk(revs))
570 die("revision walk setup failed");
571
572 traverse_commit_list(revs, show_commit, show_object, base);
573 }
574
575 return base;
576}
577
578static void show_extended_objects(struct bitmap *objects,
579 show_reachable_fn show_reach)
580{
581 struct eindex *eindex = &bitmap_git.ext_index;
582 uint32_t i;
583
584 for (i = 0; i < eindex->count; ++i) {
585 struct object *obj;
586
587 if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
588 continue;
589
590 obj = eindex->objects[i];
20664967 591 show_reach(&obj->oid, obj->type, 0, eindex->hashes[i], NULL, 0);
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592 }
593}
594
595static void show_objects_for_type(
596 struct bitmap *objects,
597 struct ewah_bitmap *type_filter,
598 enum object_type object_type,
599 show_reachable_fn show_reach)
600{
601 size_t pos = 0, i = 0;
602 uint32_t offset;
603
604 struct ewah_iterator it;
605 eword_t filter;
606
607 if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
608 return;
609
610 ewah_iterator_init(&it, type_filter);
611
612 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
613 eword_t word = objects->words[i] & filter;
614
34b935c0 615 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
20664967 616 struct object_id oid;
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617 struct revindex_entry *entry;
618 uint32_t hash = 0;
619
620 if ((word >> offset) == 0)
621 break;
622
623 offset += ewah_bit_ctz64(word >> offset);
624
625 if (pos + offset < bitmap_git.reuse_objects)
626 continue;
627
9d98bbf5 628 entry = &bitmap_git.pack->revindex[pos + offset];
20664967 629 nth_packed_object_oid(&oid, bitmap_git.pack, entry->nr);
fff42755 630
ae4f07fb 631 if (bitmap_git.hashes)
da41c942 632 hash = get_be32(bitmap_git.hashes + entry->nr);
ae4f07fb 633
20664967 634 show_reach(&oid, object_type, 0, hash, bitmap_git.pack, entry->offset);
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635 }
636
34b935c0 637 pos += BITS_IN_EWORD;
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638 i++;
639 }
640}
641
642static int in_bitmapped_pack(struct object_list *roots)
643{
644 while (roots) {
645 struct object *object = roots->item;
646 roots = roots->next;
647
ed1c9977 648 if (find_pack_entry_one(object->oid.hash, bitmap_git.pack) > 0)
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649 return 1;
650 }
651
652 return 0;
653}
654
655int prepare_bitmap_walk(struct rev_info *revs)
656{
657 unsigned int i;
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658
659 struct object_list *wants = NULL;
660 struct object_list *haves = NULL;
661
662 struct bitmap *wants_bitmap = NULL;
663 struct bitmap *haves_bitmap = NULL;
664
665 if (!bitmap_git.loaded) {
666 /* try to open a bitmapped pack, but don't parse it yet
667 * because we may not need to use it */
668 if (open_pack_bitmap() < 0)
669 return -1;
670 }
671
4d01a7fa
672 for (i = 0; i < revs->pending.nr; ++i) {
673 struct object *object = revs->pending.objects[i].item;
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674
675 if (object->type == OBJ_NONE)
c251c83d 676 parse_object_or_die(&object->oid, NULL);
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677
678 while (object->type == OBJ_TAG) {
679 struct tag *tag = (struct tag *) object;
680
681 if (object->flags & UNINTERESTING)
682 object_list_insert(object, &haves);
683 else
684 object_list_insert(object, &wants);
685
686 if (!tag->tagged)
687 die("bad tag");
c251c83d 688 object = parse_object_or_die(&tag->tagged->oid, NULL);
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689 }
690
691 if (object->flags & UNINTERESTING)
692 object_list_insert(object, &haves);
693 else
694 object_list_insert(object, &wants);
695 }
696
697 /*
698 * if we have a HAVES list, but none of those haves is contained
699 * in the packfile that has a bitmap, we don't have anything to
700 * optimize here
701 */
702 if (haves && !in_bitmapped_pack(haves))
703 return -1;
704
705 /* if we don't want anything, we're done here */
706 if (!wants)
707 return -1;
708
709 /*
710 * now we're going to use bitmaps, so load the actual bitmap entries
711 * from disk. this is the point of no return; after this the rev_list
712 * becomes invalidated and we must perform the revwalk through bitmaps
713 */
714 if (!bitmap_git.loaded && load_pack_bitmap() < 0)
715 return -1;
716
4d01a7fa 717 object_array_clear(&revs->pending);
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718
719 if (haves) {
2db1a43f 720 revs->ignore_missing_links = 1;
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721 haves_bitmap = find_objects(revs, haves, NULL);
722 reset_revision_walk();
2db1a43f 723 revs->ignore_missing_links = 0;
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724
725 if (haves_bitmap == NULL)
726 die("BUG: failed to perform bitmap walk");
727 }
728
729 wants_bitmap = find_objects(revs, wants, haves_bitmap);
730
731 if (!wants_bitmap)
732 die("BUG: failed to perform bitmap walk");
733
734 if (haves_bitmap)
735 bitmap_and_not(wants_bitmap, haves_bitmap);
736
737 bitmap_git.result = wants_bitmap;
738
739 bitmap_free(haves_bitmap);
740 return 0;
741}
742
743int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
744 uint32_t *entries,
745 off_t *up_to)
746{
747 /*
748 * Reuse the packfile content if we need more than
749 * 90% of its objects
750 */
751 static const double REUSE_PERCENT = 0.9;
752
753 struct bitmap *result = bitmap_git.result;
754 uint32_t reuse_threshold;
755 uint32_t i, reuse_objects = 0;
756
757 assert(result);
758
759 for (i = 0; i < result->word_alloc; ++i) {
760 if (result->words[i] != (eword_t)~0) {
761 reuse_objects += ewah_bit_ctz64(~result->words[i]);
762 break;
763 }
764
34b935c0 765 reuse_objects += BITS_IN_EWORD;
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766 }
767
768#ifdef GIT_BITMAP_DEBUG
769 {
770 const unsigned char *sha1;
771 struct revindex_entry *entry;
772
773 entry = &bitmap_git.reverse_index->revindex[reuse_objects];
774 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
775
776 fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
777 reuse_objects, result->words[i]);
778 fprintf(stderr, " %s\n", sha1_to_hex(sha1));
779 }
780#endif
781
782 if (!reuse_objects)
783 return -1;
784
785 if (reuse_objects >= bitmap_git.pack->num_objects) {
786 bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
787 *up_to = -1; /* reuse the full pack */
788 *packfile = bitmap_git.pack;
789 return 0;
790 }
791
792 reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
793
794 if (reuse_objects < reuse_threshold)
795 return -1;
796
797 bitmap_git.reuse_objects = *entries = reuse_objects;
9d98bbf5 798 *up_to = bitmap_git.pack->revindex[reuse_objects].offset;
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799 *packfile = bitmap_git.pack;
800
801 return 0;
802}
803
804void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
805{
806 assert(bitmap_git.result);
807
808 show_objects_for_type(bitmap_git.result, bitmap_git.commits,
809 OBJ_COMMIT, show_reachable);
810 show_objects_for_type(bitmap_git.result, bitmap_git.trees,
811 OBJ_TREE, show_reachable);
812 show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
813 OBJ_BLOB, show_reachable);
814 show_objects_for_type(bitmap_git.result, bitmap_git.tags,
815 OBJ_TAG, show_reachable);
816
817 show_extended_objects(bitmap_git.result, show_reachable);
818
819 bitmap_free(bitmap_git.result);
820 bitmap_git.result = NULL;
821}
822
823static uint32_t count_object_type(struct bitmap *objects,
824 enum object_type type)
825{
826 struct eindex *eindex = &bitmap_git.ext_index;
827
828 uint32_t i = 0, count = 0;
829 struct ewah_iterator it;
830 eword_t filter;
831
832 switch (type) {
833 case OBJ_COMMIT:
834 ewah_iterator_init(&it, bitmap_git.commits);
835 break;
836
837 case OBJ_TREE:
838 ewah_iterator_init(&it, bitmap_git.trees);
839 break;
840
841 case OBJ_BLOB:
842 ewah_iterator_init(&it, bitmap_git.blobs);
843 break;
844
845 case OBJ_TAG:
846 ewah_iterator_init(&it, bitmap_git.tags);
847 break;
848
849 default:
850 return 0;
851 }
852
853 while (i < objects->word_alloc && ewah_iterator_next(&filter, &it)) {
854 eword_t word = objects->words[i++] & filter;
855 count += ewah_bit_popcount64(word);
856 }
857
858 for (i = 0; i < eindex->count; ++i) {
859 if (eindex->objects[i]->type == type &&
860 bitmap_get(objects, bitmap_git.pack->num_objects + i))
861 count++;
862 }
863
864 return count;
865}
866
867void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
868 uint32_t *blobs, uint32_t *tags)
869{
870 assert(bitmap_git.result);
871
872 if (commits)
873 *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
874
875 if (trees)
876 *trees = count_object_type(bitmap_git.result, OBJ_TREE);
877
878 if (blobs)
879 *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
880
881 if (tags)
882 *tags = count_object_type(bitmap_git.result, OBJ_TAG);
883}
884
885struct bitmap_test_data {
886 struct bitmap *base;
887 struct progress *prg;
888 size_t seen;
889};
890
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891static void test_show_object(struct object *object, const char *name,
892 void *data)
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893{
894 struct bitmap_test_data *tdata = data;
895 int bitmap_pos;
896
ed1c9977 897 bitmap_pos = bitmap_position(object->oid.hash);
fff42755 898 if (bitmap_pos < 0)
f2fd0760 899 die("Object not in bitmap: %s\n", oid_to_hex(&object->oid));
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900
901 bitmap_set(tdata->base, bitmap_pos);
902 display_progress(tdata->prg, ++tdata->seen);
903}
904
905static void test_show_commit(struct commit *commit, void *data)
906{
907 struct bitmap_test_data *tdata = data;
908 int bitmap_pos;
909
ed1c9977 910 bitmap_pos = bitmap_position(commit->object.oid.hash);
fff42755 911 if (bitmap_pos < 0)
f2fd0760 912 die("Object not in bitmap: %s\n", oid_to_hex(&commit->object.oid));
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913
914 bitmap_set(tdata->base, bitmap_pos);
915 display_progress(tdata->prg, ++tdata->seen);
916}
917
918void test_bitmap_walk(struct rev_info *revs)
919{
920 struct object *root;
921 struct bitmap *result = NULL;
922 khiter_t pos;
923 size_t result_popcnt;
924 struct bitmap_test_data tdata;
925
926 if (prepare_bitmap_git())
927 die("failed to load bitmap indexes");
928
929 if (revs->pending.nr != 1)
930 die("you must specify exactly one commit to test");
931
932 fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
933 bitmap_git.version, bitmap_git.entry_count);
934
935 root = revs->pending.objects[0].item;
ed1c9977 936 pos = kh_get_sha1(bitmap_git.bitmaps, root->oid.hash);
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937
938 if (pos < kh_end(bitmap_git.bitmaps)) {
939 struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
940 struct ewah_bitmap *bm = lookup_stored_bitmap(st);
941
942 fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
f2fd0760 943 oid_to_hex(&root->oid), (int)bm->bit_size, ewah_checksum(bm));
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944
945 result = ewah_to_bitmap(bm);
946 }
947
948 if (result == NULL)
f2fd0760 949 die("Commit %s doesn't have an indexed bitmap", oid_to_hex(&root->oid));
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950
951 revs->tag_objects = 1;
952 revs->tree_objects = 1;
953 revs->blob_objects = 1;
954
955 result_popcnt = bitmap_popcount(result);
956
957 if (prepare_revision_walk(revs))
958 die("revision walk setup failed");
959
960 tdata.base = bitmap_new();
961 tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
962 tdata.seen = 0;
963
964 traverse_commit_list(revs, &test_show_commit, &test_show_object, &tdata);
965
966 stop_progress(&tdata.prg);
967
968 if (bitmap_equals(result, tdata.base))
969 fprintf(stderr, "OK!\n");
970 else
971 fprintf(stderr, "Mismatch!\n");
f86a3747 972
d201a1ec 973 bitmap_free(result);
fff42755 974}
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975
976static int rebuild_bitmap(uint32_t *reposition,
977 struct ewah_bitmap *source,
978 struct bitmap *dest)
979{
980 uint32_t pos = 0;
981 struct ewah_iterator it;
982 eword_t word;
983
984 ewah_iterator_init(&it, source);
985
986 while (ewah_iterator_next(&word, &it)) {
987 uint32_t offset, bit_pos;
988
34b935c0 989 for (offset = 0; offset < BITS_IN_EWORD; ++offset) {
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990 if ((word >> offset) == 0)
991 break;
992
993 offset += ewah_bit_ctz64(word >> offset);
994
995 bit_pos = reposition[pos + offset];
996 if (bit_pos > 0)
997 bitmap_set(dest, bit_pos - 1);
998 else /* can't reuse, we don't have the object */
999 return -1;
1000 }
1001
34b935c0 1002 pos += BITS_IN_EWORD;
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1003 }
1004 return 0;
1005}
1006
1007int rebuild_existing_bitmaps(struct packing_data *mapping,
1008 khash_sha1 *reused_bitmaps,
1009 int show_progress)
1010{
1011 uint32_t i, num_objects;
1012 uint32_t *reposition;
1013 struct bitmap *rebuild;
1014 struct stored_bitmap *stored;
1015 struct progress *progress = NULL;
1016
1017 khiter_t hash_pos;
1018 int hash_ret;
1019
1020 if (prepare_bitmap_git() < 0)
1021 return -1;
1022
1023 num_objects = bitmap_git.pack->num_objects;
1024 reposition = xcalloc(num_objects, sizeof(uint32_t));
1025
1026 for (i = 0; i < num_objects; ++i) {
1027 const unsigned char *sha1;
1028 struct revindex_entry *entry;
1029 struct object_entry *oe;
1030
9d98bbf5 1031 entry = &bitmap_git.pack->revindex[i];
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1032 sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
1033 oe = packlist_find(mapping, sha1, NULL);
1034
1035 if (oe)
1036 reposition[i] = oe->in_pack_pos + 1;
1037 }
1038
1039 rebuild = bitmap_new();
1040 i = 0;
1041
1042 if (show_progress)
1043 progress = start_progress("Reusing bitmaps", 0);
1044
1045 kh_foreach_value(bitmap_git.bitmaps, stored, {
1046 if (stored->flags & BITMAP_FLAG_REUSE) {
1047 if (!rebuild_bitmap(reposition,
1048 lookup_stored_bitmap(stored),
1049 rebuild)) {
1050 hash_pos = kh_put_sha1(reused_bitmaps,
1051 stored->sha1,
1052 &hash_ret);
1053 kh_value(reused_bitmaps, hash_pos) =
1054 bitmap_to_ewah(rebuild);
1055 }
1056 bitmap_reset(rebuild);
1057 display_progress(progress, ++i);
1058 }
1059 });
1060
1061 stop_progress(&progress);
1062
1063 free(reposition);
1064 bitmap_free(rebuild);
1065 return 0;
1066}